Introduction

One of the best and most reliable ways to determine the absolute ages of a material is through radiometric dating. Because of this, and because they show the age of things to be older than 6000 years, young-Earth creationists (YECs) have spent decades trying to show that it doesn’t work or just claiming that assumptions that scientists make are not true.

Their attempts at this include bringing samples of newly formed lava to a lab where they find an age of a few million years and then laugh saying that it only formed a decade ago. (Two issues there are that (1) the type of dating employed isn’t accurate for a sample younger than 500,000 years, and (2) they dated small minerals in the lava that did not melt in the original lava so actually were many millions of years old.)

Or they will claim that radiocarbon dating isn’t even used for dating dinosaur fossils … leaving out that radiocarbon dating can’t be applied to things that are more than ~50,000 years old.

Anyway, all that’s for another post. The purpose of this post is to point out that the point of science is to develop a model that can be applied to everything it attempts to describe. Gravity works the same on Earth as on the moon as in the center of a galaxy cluster. For the issue at-hand, YECs need to decide whether they believe in radiometric dating and its usable, or whether they don’t and so don’t use it.

Why Am I Talking About This?

In the news over the past week, yet another group of YECs have claimed to discover Noah’s Ark on top of Mt. Ararat in Turkey. There are many outlets for this story, but out of fun, I’ll link to the one over at FOX News. The relevance to radiometric dating? I’ll quote (emphasis mine):

“The group claims that carbon dating proves the relics are 4,800 years old, meaning they date to around the same time the ark was said to be afloat. Mt. Ararat has long been suspected as the final resting place of the craft by evangelicals and literalists hoping to validate biblical stories.”

“All radiometric dating methods are based on assumptions about events that happened in the past. If the assumptions are accepted as true (as is typically done in the evolutionary dating processes), results can be biased toward a desired age. In the reported ages given in textbooks and other journals, these evolutionary assumptions have not been questioned, while results inconsistent with long ages have been censored.”

“Creationists are not so much interested in debunking radiocarbon as we are in developing a proper understanding of it to answer many of our own questions regarding the past. At the present time it appears that the conventional radiocarbon dating technique is on relatively firm ground for dates which fall within the past 3,000 years. For periods of time prior to this, there are legitimate reasons to question the validity of the conventional results and seek for alternative interpretations.”

“A ‘Back to Genesis’ way of thinking insists that the Flood of Noah’s day would have removed a great deal of the world’s carbon from the atmosphere and oceans, particularly as limestone (calcium carbonate) was precipitated. Once the Flood processes ceased, C-14 began a slow build-up to equilibrium with C-12—a build-up not yet complete. Thus carbon dating says nothing at all about millions of years, and often lacks accuracy even with historical specimens, denying as it does the truth of the great Flood. In reality, its measured disequilibrium points to just such a world-altering event, not many years ago.”

Final Thoughts

You can’t have it both ways. Or all four ways (I kinda lost count). Either (1) radiometric dating doesn’t work, (2) radiometric dating does work once you account for things that YECs have yet to really define, (3) it does work for the recent past to 3,000 years ago but not for anything before that, or (4) it works for everything made after the flood (as in the ark was built before the flood so can’t be dated with it).

What this all boils down to is the Inconsistency Fallacy, one I didn’t address in my series the last two months of 2009 on Logical Fallacies (but I do intend to return to that series later this year). The Inconsistency Fallacy is basically summarized as, “Multiple statements that contradict one another.” For example: “Statement A is true and B is true. Use one of these statements to prove the other is false.” Or, “Bill is younger than Jill, and Jill is younger than Charles. Charles is the oldest of the three.”

And that’s the case here. Either it’s valid, or it isn’t. You can’t use radiometric dating to claim the Bible is literally true to claim that radiometric dating doesn’t work.

Let’s see if my fledgeling psychic powers are better-tuned for this one. This past week, several news outlets were running the story that the planet Venus may have active volcanism, revealed by the ESA spacecraft Venus Express (ESA press release, NASA press release, and Science journal article (the last one requires a paid subscription)). Seems like a possible story that a YEC may latch onto, so here’s another preemptive post explaining the science so if there is a YEC response, I can dive right into it without the background info needing to be repeated.

About Venus

There is some basic information about Venus that’s relevant to this discussion. First, as most people know, Venus is the second known planet from the sun, residing about 71% as far from the sun as Earth does. Conveniently, and importantly for this post, Venus has a diameter that is 94.9% Earth’s diameter. However, since its overall density is less, its mass is 81.5% that of Earth’s.

The surface of Venus is shrouded from Earth in visible light, hidden by clouds so thick that the temperature is around 465 °C, and hence you often hear that the surface is hot enough to melt lead. The atmosphere is nearly 100 times as massive as Earth’s exerting 92 bars of pressure on the surface that is the equivalent of being under about 1 km of water. Now you may have an idea why it’s hard to build a spacecraft to land on it and survive long enough to do anything useful.

The other thing about its surface is that it has been imaged, just not in visible light. The spacecraft Magellan mapped nearly 100% of Venus’s surface and determined its topography when it orbited in 1990 through 1994. Among other things, the data showed that Venus has many volcanoes, and it only has about 1000 craters.

Now you may be wondering, “Why is he talking about craters? Is it because he studies them and just thought it would be fun to mention?” Well, yeah, I do study them, but they are also the ONLY way to tell relative geologic ages in the solar system since we lack any way to absolutely determine the ages (such as through biological means on Earth and radiometric dating on Earth and the Moon). In contrast to Venus having only 1000 craters, and nearly all of them larger than 5 km in diameter, means that Venus’ surface is very young. In contrast, the planet Mars has about 45,000 craters that are larger than 5 km in diameter.

Based on a lot of modeling, current estimates of Venus’ surface cratering age shows it to be about 700 million years old. Yes, that may seem old, but compared to the moon, Mars, and Mercury – the other large, non-Earth bodies in the inner solar system – Venus has the youngest overall surface. And the last paper to really study the distribution of craters on Venus shows that they are completely random, so it’s not just that half the planet’s surface is 1 billion years old and the other half is 500 million, but the whole surface is about 700 million years old.

Catastrophic Eruptions

The next question one may logically ask is how an entire planet with a surface area 90% that of Earth’s (95%^2) can be resurfaced? From the geologic evidence of massive volcanoes across the planet, the general consensus is that it was volcanic eruptions.

Let’s look at Venus, Earth, and Mars. Mars is only 45% the diameter of Earth, and its mass is only 10%. The analogy I like to give is that if you take a little cupcake and a big cake out of the oven at the same time, which is going to cool faster? This is why Mars has long been termed “geologically dead,” though it does show some pittance of active geology today — but none from internal heat sources.

In contrast, Earth has a lot of internal heat, and we see that every day in the form of volcanoes and undersea vents. Our heat drives plate tectonics, making earthquakes that have also been in the news a lot lately with Haiti, Chili, and Mexico. So while Earth is internally molten, our lithosphere (the region below the crust and above the mantle) is thin enough and fractured enough to let some of that heat out.

The thinking is that Venus has a lot of internal heat like Earth, but, it has a thicker lithosphere. That lithosphere under normal circumstances is simply too thick to let heat escape, so the heat stays trapped inside.

Now here’s another analogy: Let’s say you’re going to spend another lonely night in your 1-bedroom apartment, and even the cat doesn’t want to have anything to do with you. You’re going to watch a cheesy movie and don’t want to cook, so you go to the freezer and look through your few dozen frozen microwaveable dinners that you bought in bulk at Costco. You choose one and read the directions for lack of anything better to do. The directions state quite clearly: “PUNCTURE WRAPPING BEFORE MICROWAVING.” From past experience, you know that if you don’t, the heat will build up and explode in what means 10 minutes of messy clean up. But if you do puncture the wrapping, the steam can escape and it’s all good.

This is the same – albeit simplified – thing that happens with planets. Since Earth can release its heat, it doesn’t “explode.” With Venus, the thought is that since the lithosphere is thicker, the heat builds up until the molten rock finally forces its way out. When it does, the lithosphere cracks and planet-wide, catastrophic volcanism ensues. And the last time this happened – based on the craters – was around 700 million years ago.

Fascinating … What Does This Have to Do with the Press Release?

Good question, I’m glad you asked. Let’s get back on-topic. With a last massive planetary resurfacing 700 million years ago, one question has been, “Is this going to happen again?” Another is, “How often does this happen?” And the most relevant to this discussion, “Is there still some dribble of volcanism today?”

It’s that last question that Venus Express may have found evidence to answer in the affirmative. From the NASA press release: “For the first time, scientists have detected clear signs of recent lava flows on the surface of Venus. The observations reveal that volcanoes on Venus appeared to erupt between a few hundred years to 2.5 million years ago. This suggests the planet may still be geologically active, making Venus one of the few worlds in our solar system that has been volcanically active within the last 3 million years.”

I’m guessing they had to add “one of the few” because of Earth and Io.

Anyway, going off of the press release (I don’t have access to the Science article right now — I’ll update this later if needed when I get ahold of it), the researchers were able to study the mineralogy on three of Venus’ volcanoes. The mineralogy matches that on recent volcanic eruptions from some volcanoes on Earth, like Hawai’i. On Earth, the rock’s reaction with oxygen quickly changes the mineralogy, and hence the research strongly suggests that the flows are young enough to not have been modified. They suggest anywhere from a few hundred to 2.5 million years old.

This may change the picture that I outlined above of the catastrophic volcanism. In perhaps the more controversial part of the press release to me, they suggest that this could indicate the volcanism on Venus has been gradual throughout time – in a kind of steady state situation where localized events happen to resurface the area and cover a few craters, die down, and then happen elsewhere, but not covering enough to maintain the 700-million-year-old crater surface age. It’s a possibility, but at least to me they will need to show more evidence before I find it more convincing than the catastrophic scenario.

What’s this to Do with Young-Earth Creationism?

In this case, I am guessing that if some YEC person or institute chooses to use this to try to add evidence for their claims it will be along the lines of, “Since Venus has active volcanism today, it must have been created in the very recent past – 6000 years ago. Evolutionists/Darwinists/Evilutionists will have to completely change their thinking in order to reconcile an active Venus with an old-Earth.” Or something like that.

Final Thoughts

We’ll see if my budding psychic powers have been led astray again. I hope not, but we’ll see. Even if they have, hopefully I’ve given you enough information to find this press release interesting and have newfound interest in the field of planetary geology and geophysics.

Introduction

In the early days of 2010, specifically January 4, I read an article on Wired Science entitled, “Age of Solar System Needs to Be Recalculated.” After having written this blog for nearly a year and a half and having a fair number of posts about young-Earth creationism (YEC), I read the article knowing that it would just be a matter of time before someone at either the Institute for Creation Research (ICR) or Answers in Genesis (AiG) would use the article to effectively say, “Look! See!? Scientists don’t know what they’re doing, all of radiometric dating is wrong, creationism is right!” And they didn’t disappoint, though I have to admit it took longer than I thought it would (17 days).

The VERY Basics of Radiometric Dating

The process of radiometric dating and all its corollaries and techniques could likely fill a decent-sized graduate textbook. That’s not the purpose here, rather it’s to give you the most basic information so you can understand the issues at-hand.

The principle behind radiometric dating is that every atom has many different isotopes. An atom is made of protons, neutrons, and electrons. The number of protons determines what atom it is (1 proton = hydrogen, 2 protons = helium, etc.). The number of neutrons determines the isotope (1 proton = hydrogen-1, 1 proton + 1 neutron = hydrogen-2 (deuterium), 1 proton + 2 neutron = hydrogen-3 (tritium)). The electron number determines the ionization state, which is unimportant for this discussion.

Atoms that get too heavy are inherently unstable. If you cram too many protons and neutrons into the center, the atom will decay. If you cram too many neutrons into an already stable isotope of an atom, it will decay. “Decay” is when it releases either one or more of its neutrons or protons by turning it into something else. That decay time is based purely on fundamental physical laws and constants, it is a quantum mechanical process, and it is different for all isotopes.

The time over which half of a sample of an isotope will decay into another is called the “half-life.” After two half-lives, 75% will have decayed; after 3, 87.5%, after 4, 93.75%, etc. (1-0.5# of half-lives). Half-lives can be measured over human timescales, and/or they can be correlated with other established dating mechanisms, such as ice-cores, tree rings or written records.

An assumption of radiometric dating and necessary corollary is that the sample is from a self-contained system. In other words, it has to be “original;” if the sample was contaminated some time after it formed, then the dating will be thrown off. Similarly, we need to know how much of the original “parent” isotope was present relative to the “daughter” isotope so that the amount of original daughter isotope can be removed from the equation.

What the Original Science Article Found

The Wired Science was reporting on an article from Science News, which itself was reporting on an article published in the journal Science at the end of 2009. (Unfortunately, you have to pay for the article unless you are at an institution that has a subscription. The citation is, Brennecka et al. (2010). “238U/235U Variations in Meteorites: Extant 247Cm and Implications for Pb-Pb Dating.” doi: 10.1126/science.1180871. An earlier abstract of their findings can be found for free here.)

It had been assumed for years that the amount of original uranium-238 and uranium-235 in asteroids was even throughout all the asteroids. This had been measured independently many different times and the ratio had been the same. However, there is no theoretical reason why this should be true, and so people kept measuring it to continue to check the results. What these researchers found was that, actually, when measured more accurately and taking a few more things into account, that there actually are slight differences and the ratio isn’t quite what it was thought to be.

What does this do? It changes the age of the solar system by 1 million years. So it could be either 4.566 or 4.567 billion years old.

One of the co-authors explicitly states, “It’s not as if this age-dating process doesn’t work anymore,” says coauthor Ariel Anbar, also of Arizona State. “But if you want to push this isotope system to get ages that are really precise, suddenly we realize that there’s this variation you need to take into account.””

What they did not find is that radioactive decay rates are not the same within a given isotope. As I stated above, that is set by the fine-structure constant of the universe and purely quantum mechanical processes.

Enter the ICR’s “Science” Writer, Brian Thomas

The very first sentence of ICR’s January 21, 2010 article, “It’s Official: Radioactive Isotope Dating Is Fallible,” states: “New data collected by secular researchers has confirmed what creation scientists discovered decades ago—geologists’ cornerstone assumption that the rate of radioactive decay is constant over time is not correct.”

Except … NO! That was NOT what the article nor paper nor abstracts nor researchers said.

Moving on … the third paragraph starts with, “Gregory Brennecka of Arizona State University and colleagues measured the relative amounts of Lead 238 to that of the stable Lead 235 from several samples taken from the large Allende meteorite, named for the village in Mexico near where it landed in 1969.”

Again … NO! They used uranium-238 and uranium-235 as a proxy for lead-206 and lead-207.

Next paragraph: “The differing amounts of material that were found in separate samplings of the same meteorite should not have been detected if isotopic decay of Uranium is indeed stable over time.”

NO! The parts of the same meteorite that the researchers analyzed are almost guaranteed to have formed at the same time because – in part – they are in the same meteorite. Therefore, if the rate were to change through time, then they all should still show the same ratio of parent to daughter isotope because they all would be changing at the same rate. Therefore, what it shows and what the researchers concluded is that the original ratios were slightly different.

Brian Thomas, the ICR article’s author, goes on a quote-mining expedition for the next two paragraphs to try to show that radiometric dating was never an established thing.

He then goes on the expected, “But creationists knew it wasn’t!” by stating, “For years, creation researchers have published ample data to refute the assumed stability of nuclear decay rates in general, as well as specifically for Lead.” (Again missing the actual point it was uranium that they were analyzing.) He continues with standard YEC arguments after that.

Final Thoughts

Thomas closes with: “Although Brennecka and his colleagues detected only a small difference in the same Lead isotope amounts in the same rock, this was quite enough to falsify any notion that this Lead 238 decays at a constant rate into Lead 235. And this dovetails with other valid research which found similarly falsifying data.”

This is a standard creationist tactic: (1) They find anything that is an iterative step in science (in this case refining an established dating mechanism and showing that at the 0.1% level there are additional issues to take into account). (2) Misrepresent it. (3) Find supporting quotes through quote-mining that shows that “even secular scientists” had doubted the technique. And (4) therefore God did it 6000 years ago.

Post-Script, January 27, 2010

Every quote presented above was copy-pasted from the original ICR article. The next day, I was notified in the comments section below that the article had been revised “for accuracy.” As it now reads, every quote that I took has been either slightly or wholly changed. The most obvious is that they have fixed the “lead 238/235” to make it uranium.

But perhaps more interestingly, the language is less scathing. For example, the opening paragraph is now, if one were to show the edits via strikethroughs and insertions:

Is it just me, or does that actually seem to be a softening of the language? It actually seems to represent the research now.

Then there’s this one:

“The differing amounts of material that were found in separate samplings of the same meteorite should not have been detected if isotopic decay of Uranium is indeed stable over timewere unexpected.”

Again … the language seems softer and actually seems to represent the research. The rest of the article is still effectively, “This calls all radiometric dating into question,” but at least it’s not based on quite an obvious straw man. Thank you KT_trebor for pointing out the revision!

The purpose of this particular post is a follow-up on that first one. In the first one, I wrote that the video sample on the CreationAstronomy.com blog is approximately 13 minutes long. However, I was only able to view about 4 minutes of it for free from the website. Well, one of the readers of my post sent me a link to download the full section of the video.

So, without further ado, let’s examine the claims in the next 9 minutes of the video.

The Rest of Psarris’ Claims

1. “The more we study Jupiter, the more evolutionists have realized it doesn’t fit into their models.” He then shows another quote from Richard Kerr (the same author he quoted from out of context in my first post on the subject) stating, “… no one has a satisfying explanation of how they were made.” Psarris then states that, no, that’s not true, “the Bible has a very satisfying explanation of how they were made.” (3 min 50 sec)

2. “Jupiter has over 60 moons; they pose problems for evolution, too.”

2.a. “Ganymede has one of the most bizarre surfaces in the entire solar system. … Evolutionary models predicted that Ganymede couldn’t have a magnetic field. But when our space probes arrived and started taking measurements, we found that it does have a magnetic field.” (4 min 30 sec)

2.b. “Then there’s Callisto. This moon is the most heavily cratered object in the solar system. Evolutionists believe that it has one of the oldest surfaces of any object, about 4 billion years old. It was a real surprise, then, when our space probes took some close-up pictures.” It was expected that there would be many small craters, but there was a lack of them. Also, “some of the pictures show what appears to be fresh ice on Callisto’s surface, … [but] evolutionary models say Callisto is old, cold, and dead.” (5 min 30 sec)

2.c. “Next, there is Europa. … Europa is the smoothest [object in the solar system]. … [The ice on Europa] is several miles thick, but some scientists think there might be liquid water beneath it. And where there’s water, there has to be life, right?” Apparently in a previous video section he addressed “how ridiculous that idea is,” but Psarris goes on to say, “you still hear it in the news a lot: Somebody finds a new crack on Europa, and thinks, ‘Ooo! Look! Water might ooze into the crack, and there could be life evolving in the water!’ Then some reporter runs a story about it saying we’re on the verge of finding life elsewhere in the solar system even though all we found was a crack in a moon.” (6 min 30 sec)

2.d. This claim deals with craters on Europa, about which he makes a claim straight from the Institute for Creation Research (I know this because I already debunked this claim before): “Because Europa has only a few craters, we’ve been able to study them closely. One recent study has shown the evolutionary model for cratering is all wrong.” He goes on to explain that it’s apparently wrong because a single crater forming can create up to a million or so smaller, secondary craters (formed by debris from the primary crater event). Because of this, he makes the claim that you need fewer impactors to make all the craters we see, which then implies a younger age than “all these billions of years.” Psarris then extrapolates this to Venus and the moon. (I’m not going into significant detail here since I’ve addressed it extensively before, and I’ll talk about it in my next section where I address these claims.) (7 min 10 sec)

2.e. For the last of Jupiter’s large moons, Io, Psarris makes light of the massive volcanism on Io’s surface. Psarris’ main claim is simply that Jupiter’s tidal heating of Io is not enough to account for all the heat, so some of it must be left-over from its formation which means it formed recently. (9 min 15 sec)

2.f. The second of the Io claims is that, given the amount of lava that is erupting, Io must have completely recycled itself 30 times in the ~4.5-billion year history of the solar system. (10 min 30 sec)

2.g. We get a third claim out of Io: Apparently, astronomers were “flabbergasted” to learn that the temperatures of the lava on Io reaches 3000°, when it only reaches 2000° on Earth. Also, the lava is dense when it should be formed of low-density material by this point due to simple differentiation (heavy stuff sinks). (11 min 20 sec)

The rest of the video (post-12 min 15 sec) is a review of all the points that Psarris makes. But, there are some typical statements at the end:

“Evolutionary models fail utterly to explain Jupiter.”

“Building Jupiter has long been a problem for theorists.” (Wetherill, 1995)

“I don’t think the existence of Jupiter would be predicted if it weren’t observed.” (Wetherill, 2001)

“Why do they still cling to a broken model? Because when you reject the Truth, you have to accept a lie.”

“Pity the poor evolutionist, who is so committed to a bankrupt theory that he can’t see the hand of his creator in this majestic planet.”

Addressing the Remaining Claims

1. No Models Explain How Jupiter Formed

This is simply not true, and at its nicest level is taking statements out of context and sorely downplaying the status of solar system formation modeling. I address this quite a bit in my first post in this 2-part series.

The other aspect of this claim that deserves to be addressed is the very common “god of the gaps” logical fallacy: “We don’t know how this happened, therefore God did it.” Among the skeptical community, this often is compressed into the single word, “goddidit,” because we hear it so often from Creationists. The basic fallacy here is that you confuse something that we don’t currently know with something that we can’t possibly know, and therefore it is only explainable through the miracles that a divine creator can make.

2.a. Ganymede

Ganymede’s magnetic field is interesting. But, as I stated in my first post about this CreationAstronomy.com site, that’s what makes astronomers happy! We like it when we find something that we can’t immediately explain. If nothing else, that means Job Security! But on a more explanatory level, the theory for the formation of a magnetic field on a planetary scale is that it requires a molten interior, but Ganymede shouldn’t have one by this point in its life because it should have cooled. On that point, Psarris is correct. But, what does this mean, then, for an explanation?

It means that we need to explain how Ganymede’s core could have either remained warm until at least 1 billion years ago or was heated up until about 1 billion years ago (since a remnant field can still exist for ~1 billion years even without something actively driving it). What modelers have come up with is that the main jovian satellites were not always in their current orbits, but that they slowly migrated into them. This migration passed through resonances until it got to its current resonance of 1:2:4 (Io, Europa, Ganymede … Callisto isn’t really in a resonance (yet)). Getting into this resonance caused enough tidal heating to create a dynamo in Ganymede’s core. In other words, there’s a perfectly reasonable dynamical model that explains this without resorting to goddidit.

2.b. Callisto’s Lack of Small Craters

This is another (almost) true observation about Callisto: It does lack as many small craters as were predicted from simple cratering models. Note here that “small” is ~1 km sized craters and smaller. Before I get into possible explanations, though, I have to pose the likely rhetorical question: How does a lack of small craters prove the solar system is young? I honestly don’t see how it has any relevance to it, other than under the quite childish false dichotomy notion that, “if I can show you’re wrong, then I must be right!”

What this implies, however, are a few different things. One idea is that the main impactor population of Callisto – possibly comets – simply lacks a small size population (impactors a few 10s to 100s of meters). Personally, I don’t find that explanation incredibly convincing from my own research in craters, however. Another possible explanation (Bierhaus et al. (2000) “Small Crater Populations on Callisto”) is that it is simply a resolution issue, and that when viewed under higher resolution, previously indiscernible small craters become evident.

There are also other possible explanations here, but my main point is one that I’ve been stressing when dealing with this CreationAstronomy.com website: A lack of conforming to known, simpler models is something that astronomers – and scientists in general – like, because it means that they then get to go and figure out a new model to explain the new results.

2.c. Europa -> Liquid Water -> Life?

This claim is one that I’ve addressed before, namely in my post, NASA’s “Follow the Water,” Ice Detected by Phoenix on Mars, and Noah’s Flood. It’s one of my older posts so not as well organized, but the basic idea is that all life that we know of needs liquid water to live. Therefore, the first step in attempting to find life is to find places where liquid water is. It’s that simple.

2.d. Europa and Secondary Cratering

This is another claim that I have addressed, in-depth, before. The post is, Dating Planetary Surfaces with Craters – Why There Is No “Crisis in Crater Count Dating”. Psarris’ claim really is identical to this ICR article. The basic response boils down to: Astronomers know of the issue. And we take it into account. It’s another of the classic creationist tactics where they will give you a problem with “evolutionary” science and then say it invalidates everything about science, but they don’t tell you that we already know about the issue and take it into account.

2.e. Io Is Too Hot

Says who? I have not heard nor seen this claim before, and I took a graduate class from the guy who literally wrote the book on Jupiter’s moons. If Psarris would like to show his calculations, I will gladly look over them and get back to this claim.

2.f. Io Is Erupting Too Much

While the basic idea behind this claim is not new, I have never seen it before raised as an issue. Planetary crust is recycled. Stuff coming out of volcanoes on Earth now used to be buried miles beneath the surface which used to be on the surface. I’m sorry, but I honestly don’t see the issue here with this claim.

2.g. Io’s Lava is Too Hot and Too Dense

First, I just love it when articles say that scientists are “flabbergasted,” “surprised,” “shocked,” “astounded,” “puzzled,” “clueless,” “can’t understand,” “unbelieving,” “amazed,” “bewildered,” “baffled,” and other such phrases. (Okay, more honestly, I really don’t like it.) Seriously, we’re apparently the people who are supposed to know everything and so it’s like a “gotcha” game when there’s a discovery that “surprises” us. Need I repeat it? THAT’S THE POINT OF SCIENCE — TO FIND OUT NEW THINGS!

Alright, deep breath … now, what about the temperatures of Io’s volcanoes. Again, I do not know of why this is particularly an issue. If Psarris would like to show his math – or show someone else’s as to why magma cannot be heated to 3000° on Io, I will take a look at it. But this is another case where I do not particularly want to do his work for him to then add more work to my own plate.

Final Thoughts

I’ll start off by saying that I threw this post together rather quickly (if “quickly” can mean an hour of writing and looking things up and watching the video segment), so I apologize if I seem a little flippant at the end, brushing off his claims.

However, my point really is the same: If he is going to make the claim, he needs to back it up. You can’t just state something and leave it at that and expect people to bend over backwards to flesh out your own claim and then go to the trouble of pointing out why it’s wrong (if it actually is). And at least with the few physics things that Psarris addresses (basic thermodynamics), he needs to show the math. Otherwise, it holds as much weight as me saying that my oven can’t possibly heat up past 500° by itself therefore it contains heat left over from its formation which means it’s young.

Otherwise, I hope that at the very least this post will lead you to question the validity of Psarris’ claims. And if you’re already a firm critic of young-Earth creationism, then I hope that I have armed you with more information to stop the spread of bad pseudo astronomy.

Introduction

In the last few days, I’ve seen a few blog posts about Saturn being a young system on the usual creationist sites or those responding to the creationist sites, and being a bit behind in my blog, I thought I’d check out the usual suspects. Predictably, I found the article posted yesterday, May 7, 2009, on the Institute for Creation Research by my own favorite, Brian Thomas (who I picked apart in this blog post.

The article in question now is entitled, “Planetary Quandaries Solved: Saturn Is Young.” Okay, I admit I needed to take a deep breath with this one before reading it. After all, you’d think that if scientists had really discovered that Saturn had been created/formed recently, it would be all over the news, right? So right off the bat, the title is misleading, but understandable for a creationist website.

Then I picked through some of the references. Why? Because I actually do research on Saturn’s rings. I will be submitting revisions to a 50-page manuscript to the journal Icarus in the next 3 days that should be published in a special edition of the journal at some point this summer, and the conclusions from my simulations are that the ring system is at least 2 times as massive as before, likely more, and the implications are that the system can then easily be a corresponding amount older (e.g., at least 2 times older).

And, lo!, one of the references in the article directly cites my work — a ScienceNews article from September 2008. (Check out paragraph 4 of the article.) So now, it’s personal — Brian Thomas is using MY research (in part) to advance his creationist agenda, and I will not be silent about it. Hence this blog post. 🙂

What Is the Evidence the Saturnian System Is Old?

Let’s ignore all of the outside evidence that it’s old. Let’s ignore solar system formation models. Let’s ignore standard conventional wisdom. Let’s ignore the scientific problems about biblical creation. What is the evidence that the system is old, or at least not young.

Well, being a crater counter when I’m not running simulations of Saturn’s rings, I point to craters. Craters are used throughout the solar system as the only cross-planetary method of relative dating methods. In other words, how many craters a solid object has is the only thing that we can measure, at present, that gives us the relative ages of two solid surfaces.

Crater ages have been calibrated via Apollo lunar sample returns, and so – at least for our moon – we know that a certain number of craters per unit area corresponds with one age, and a different number corresponds with a different age — and we know what those ages are to reasonable accuracy for the moon.

Much work has been done and is being done to try to extrapolate what we know from our moon to other solid bodies, including Mercury, Venus, Mars, and the giant planets’ satellites. While the work isn’t perfect and uncertainties remain, the state of the research is that we can tell the difference between an object that is 6000 years old or 4 billion years old.

The surface of Titan? The last number I saw is that there are around 150 impact structures that have been observed, so the present-day surface age of Titan is reasonably young. Yes, I admit that — I’m not hiding it.

What about the surface of the other moons, such as, say, Iapetus? Well, take a look at the image to the right. There are A LOT of craters there, and the surface age of Iapetus is likely on the order of a few billion years (I say “likely” because I haven’t actually done the crater counts there). Now, unless you’re going to engage in some very special pleading, this is pretty good independent evidence that at least some parts of the Saturnian system is old.

Enter the Argument for Youth: Saturn’s Rings

I grew up reading that Saturn’s rings were young – probably formed only 100 million years ago after the breakup of a medium-sized moon, about the size of Saturn’s moon Mimas (shown on the right). That was based on a few things, including estimates of its mass from Voyager data as well as spectroscopic observations showing that the rings are fairly “fresh,” showing relatively little contamination by, basically, space dust.

This was still the predominant idea in 2002, when Jeff Cuzzi made his quite that Brian Thomas uses in the second paragraph of this article:

A history of mystery surrounds the youthful features of Saturn’s rings. Jeff Cuzzi, a planetary scientist at the NASA Ames Research Center, said in 2002, “After all this time we’re still not sure about the origin of Saturn’s rings….There’s a growing awareness that Saturn’s rings can’t be so old.” Cuzzi said, “There are two reasons to believe the rings are young: First, they are bright and shiny like something new. It’s no joke.” Indeed, after millions of years, the icy rings should have collected so much space dust that they should be charcoal-colored by now. Second, after only a few million years, the little moons embedded among the rings should have “flung away. This is a young dynamical system.”

And, this was still an issue in 2006, when I was just starting my simulations. The third paragraph of this article cites Josh Colwell in a presentation he gave. He was listing some of the current problems in a few-billion-year-old rings system, but the problems were still based on old data estimates for both the mass of the ring system and the viscosity of the particles (viscosity can be thought of as how well particles can transfer energy from one to another or how well they flow — water is not very viscous but molasses is).

Enter the simulations. I use Mark Lewis’ code for these simulations, and I make a point of that because Mark is quoted in the fourth paragraph of the ICR article:

Mark Lewis of Trinity University in San Antonio cautioned that it is still not known how they really clump. “It isn’t as straightforward as saying that high-density particles would lead to more clumping.”

This is true. There are many different parameters that go into these simulations to model the physics involved. Even though I explored a huge range of parameter space in my simulations, performing over 150 different N-body simulations that took over 27,000 CPU hours to run, I still did not explore the whole range of space, and a few of those parameters do affect how ring particles clump together.

Clumping is important because it directly affects how we estimate the mass of the rings. If the rings do not clump at all, then for every particle it will block an equal amount of light. Kinda like if you spread a lot of sand on a sheet of paper and you spread that sand evenly around, you will only see a little of the paper through the sand. But, if you use the same amount of sand and start to make little sand piles, you will see more and more of the paper.

That’s how we estimate the mass of the rings – by how much paper (how much light) can be seen through the rings. And, if the ring particles are clumped together, then you need many more ring particles to get the same amount of light blocked. What my simulations show is that clumping plays a much larger role than previously thought, and so we need more material in the rings to match the observed light-blockage.

Why do more massive rings mean that the ring system is older – or can be older? Because more massive rings means the viscosity is higher and so they spread out more slowly (one of the arguments they were young is that they would spread out too quickly). Also, it means they can be older because the same amount of pollution will get spread out over a larger area, and hence they won’t be as “dirty.” So, arguments that they are young because they don’t show a large amount of pollution can be answered that the pollution is just better hidden than we thought because there is more material within the rings to get polluted.

What was the connection to me here? Well, they’re my simulations. And that fourth paragraph has a quote from an article that talked about my results. Hence why I take this a little personally.

Moving On to Enceladus

In paragraph 5 of his article, Brian Thomas says that Saturn’s moon Enceladus “shows no hint of being 4.5 billion years old, but instead appears remarkably young.” I’m not going to harp on Brian’s grammar mistake here because I’m sure I have made my fair share of mistakes in this article grammar-wise, but I will say that it’s a poor journalist who doesn’t know what a sentence fragment is.

Anyway … this statement is simply wrong. It is true that the geysers that were discovered coming from Enceladus’ south polar region were a surprise, and they have made many people in the planetary community excited to find out why they are there. (Note – yes, new discoveries that challenge old models make scientists happy, not upset, as creationists would have you believe.) And a lot of Enceladus’ surface does appear to be young. However, a fair portion of the surface also appears to be very old, as shown in the picture on the right. Yes — I’m talking about all those craters.

Final Thoughts

That’s really the point of this article. So, no, the planetary quandary has not been “solved” to say that Saturn is young. Rather, the ring system can still easily be old based on the latest (and if I do say so myself, the greatest) simulations, and even though some features of Enceladus appear young and active, there are other parts of the moon that tell the tale of being ancient.

This entry is in specific response to the “Venus vs. Uniformitarianism” article from the Institute for Creation Research, written by David Coppedge.

This is meant to be a short post on the heels of my crater discussion from yesterday, and it actually fits in fairly nicely even though it’s about something completely different: The planet Venus.

Venus is an interesting planet and has held peoples’ imaginations ever since it was realized that it was shrouded in clouds, hiding its surface from view. At almost the same size as Earth, it was long thought of as Earth’s twin and it may hide a paradise beneath the atmosphere. That view vanished in the 1960s when spacecraft showed it to be a planet with a surface temperature far above the boiling point of water, the clouds full of sulfuric acid, and the atmosphere so heavy that the surface pressure is the equivalent of being under 1 km of ocean on Earth.

But another highly unexpected observation was that Venus’ entire surface seemed to be the same age based off of the crater population (see, there is a link to my post yesterday!). There are just under 1000 craters on Venus, and statistically they are distributed randomly over the planet, no region being older nor younger than another (to the accuracy of crater age dating). And then, based off of the crater density, the surface age of Venus was estimated to be 500 million to 1 billion years old (the agreed-upon number today is about 700 million).

(Note that a pretty good, definitive paper on this is found in the Journal of Geophysical Research, vol. 97, No. E10, from 1992 in an article by Roger Phillips et al. entitled “Impact Craters and Venus Resurfacing History.”)

The question is: What would make the entire surface a single age, between 11-22% the estimated age of the solar system? That brings us to the Institute for Creation Research article I cite at the beginning of this post. David Coppedge uses Venus to say that it “poses a serious challenge to uniformitarian views,” (views that say geologic history has resulted from the action of continuous and uniform processes throughout time; in other words, the opposite of catastrophism).

This is actually true. It’s very difficult to think of a uniformitarian process that would produce what we see on Venus today. That’s actually why no one really does (hence, it is a straw man argument, an argument against something that the other side doesn’t actually say). The prevailing view today is that Venus’ current surface is the result of a catastrophic release of magma from within the planet that broke through the crust and covered the planet in a geologically short period of time – hundreds or thousands of years.

The proposed mechanism is that without plate tectonics to release heat and energy, the build-up in the planet’s mantle eventually overpowered the strength of the crust, resulting in the catastrophic release. It is possible that this is cyclical, occurring once every few hundred million or few billion years – we just don’t know because we (a) haven’t seen it and (b) we can only see the evidence from the last time.

Why this becomes important to creationists, and why it’s on the ICR website, is two-fold. First, creationism relies upon catastrophic events to explain geologic features like the Grand Canyon (general appeal is to Noah’s Flood).

Second, which is the point of the last two paragraphs of the ICR article, is, “One idea never considered is that the missing 90% never occurred.” So he is arguing for a young solar system based on the data showing that Venus’ surface is ~700 million years old. There are many, many things wrong with this argument, but for the sake of my promised brevity, I will only address two.

The first should be obvious: For creationist arguments, the goal is to get the age of the solar system down to 6000 years or so. However, it shouldn’t take a math major to figure out that 700,000,000 is much greater than 6000 … by a factor of over 100,000. The point of the article is more likely to try to make the reader second-guess the “millions of years” arguments rather than have the reader actually think of the timescales that are being suggested.

Second, and this is more subtle, he is still relying upon an argument from crater age dating. This has been calibrated from the Moon. So let’s say that the lunar timescale were off by, oh, a factor of 1,000,000 (what’s needed to get it to 6000 years). Remember from my post yesterday that crater age dating is relative, and so that would mean that Venus’ age (since the article is suggesting that its surface age is the same age as the planet) is also younger by a factor of a million.

That would place Venus’ age at between 500 and 1000 years old. Not even creationists think that Venus is that young – they can’t, because there are historic records dating back over 4000 years showing observations of Venus. As you can see, if you actually think about these arguments logically, and carry them through to their conclusion, they become unrealistic unless there is some sort of “other” special happenstance. You can’t pick and choose how far you want to take the evidence, as they do in this article.

Finally, I want to end with two comments on the last paragraph of the article. First, “If it were not that Darwinian evolution requires vast ages …, many of the features observed by the space program would be considered young.” This is not true. Geologists had already figured out Earth was at least on the order of millions of years old before Darwin ever presented his theories on evolution. Geology in terms of figuring out how old things are has absolutely nothing to do with biological evolution. It has much more to do with basic physics, such as heat transfer, collision rates, gravitational perturbations, etc. Nothing in space is dated based on an idea that evolution says something has to be old … this is an absolutely ridiculous claim showing naïveté, especially coming from someone who “works in the Cassini program at the Jet Propulsion Laboratory.”

Now that I have that out of my system … second, a more philosophical point: “Should scientists be allowed to infer histories that are indistinguishable from myth?” Speaking as a scientist, the idea that I can or can not formulate a history from on my observations based on the whim of whether someone else thinks I should or shouldn’t be allowed is very … irritating. Who is he to say whether someone can or cannot think something?

Science works by lots of people coming up with lots of different possible explanations based on the observations. They can then test those explanations by making predictions for further observations, and those observations should be able to rule out some of the explanations and still allow others. Then the process repeats until (hopefully) one is left that explains all the observations. If none do, then a new hypothesis must be built that can explain all the observations, and then be further tested.

The “catastrophism” idea for Venus is not presently testable due to financial and technological constraints. However, there are ways that it can be. One would be sending ground-penetrating radar to Venus to peer within its crust and determine heat flows. Another would be to find fissures across the planet that could be outlets for the resurfacing material. A third would be to actually date material on the surface and to dig down within the crust and date that material, as well. The argument from the article – that the first 90% of Venus’ history never actually existed – is not testable at all, nor does it make sense in the context of the rest of the solar system (as discussed in my demonstration that Venus would need to be 500-1000 years old based on this article).

This entry is in specific response to the “Crisis in Crater Count Dating” article from the Institute for Creation Research, written by David Coppedge.

How can astronomers say that Mars had recent volcanism? Or that the surface of the moon Io is younger than 50 years? Or that the youngest stretches of terrain on our moon’s surface dates back to about 3 billion years ago? The answer is one of the basic tools of comparative planetology: Impact craters.

Impact craters are ubiquitous throughout the solar system – every single solid body has craters on its surface except for the moon Io (because its surface is so young due to the incredible amounts of vulcanism). Impact craters form when an impactor – like an asteroid or comet – hits the target surface of a planet or moon. The impact occurs at high speed, and the final crater depth, diameter, and shape are effectively determined by the surface gravity, the mass of the impactor, and the velocity of the impactor. Almost all impact craters are circles; only impacts at very low angles (less than 10°) will form elliptical craters.

Note: There are craters of other origins, such as pit craters or caldera craters at the top of volcanoes. Only impact craters are used to date surfaces, and for brevity I will only be referring to them from this point on as “craters” instead of “impact craters.”

The basic idea behind using craters as an indicator of a surface’s age is that the longer the surface is around, the more craters will form. If an impactor were to hit a target at a rate of 1 per year, then a surface that’s 1,000,000 years old should have 1,000,000 craters. But if that surface were to have something happen to it, like it got covered by lava, then that would erase the craters and the crater age would be set back to 0.

That’s effectively what people do in order to date the surfaces of planets or moons that are not Earth: We count the number of craters of different sizes for a part of the surface and then compare that with the rate of impacts of that size. This is called “crater age dating,” and it is a form of “relative age dating.” The reason that it’s relative is that it cannot give an absolute age in years, it can only say if a surface is statistically older or younger than another surface.

To actually calibrate the number of impactors of a given size to an absolute age requires us to date the rocks within that surface. This was one of the science results from the Apollo lunar missions – samples brought back from the moon were dated in the lab and hence an absolute age could be assigned to surfaces with a certain density of craters (number of craters per area). This can then be extrapolated to other locations in the solar system.

Craters form in all sizes – from microcraters on airless bodies like the moon to giant basins literally 1000s of kilometers across. In general, researchers use craters that are on the 10s of meters scale to about 1 kilometer, or a few kilometers to a few 10s of kilometers for age dating (at present, there is a general mismatch gap in what is used; this is generally because the meter-scale craters are used to date smaller, isolated surface areas whereas kilometer-scale craters are used to date much larger geologic units that cover a significant percentage of the planet or moon).

One more piece of background information is that when craters form, they send up clouds of debris, from dust-sized particles to objects up to a few percent the size of the original impactor. These larger chunks of material are ejected outwards from the forming crater, and they may end up forming their own craters. These are called secondary craters since they were formed as a result of the original, or primary crater.

Secondary craters are different from primary craters in the way they look because of their formation history — mainly they are much smaller and they are also shallower. This is both because the ejected material that formed them was much smaller than the original impactor and because the velocity of the debris is much less than the original impactor, so there is significantly less energy to form the secondary crater. Observations and computer models have shown that the largest secondary craters can only be up to ~5% the diameter of the primary crater (observations made on Earth, Moon, Mars, Mercury, and Europa), although the vast majority are much smaller than 1% of the primary. In addition, secondary craters that form closest to the primary (within about 10 crater radii) are usually very easy to identify as secondary due to the way they look and the surrounding surface.

The point of this background it that crater age dating has been used for over 50 years, and it rests on very solid theoretical, experimental, and observational grounds. However, you wouldn’t think that given the ICR article, “Crisis in Crater Count Dating:” “New thinking about ‘secondary craters’ has thrown this whole foundation of comparative planetary dating into disarray.”

The article continues with misleading statements: “One writer in Nature estimated that a single large impact on Mars could generate 10,000,000 secondaries, and that 95% of the small craters on Europa could be from fallback debris.” You are clearly expected to infer from this that almost all craters (95%) on surfaces are secondaries by simply connecting those two phrases together. That may actually be true. But there is no size range stated.

Those same authors, Alfred McEwen and Edward Bierhaus, who are not mentioned in that quote wrote a paper in 2006, “The Importance of Secondary Cratering to Age Constraints on Planetary Surfaces,” in the Annual Review of Earth and Planetary Science. I highly recommend reading it if you are interested in this subject, and it is written at a non-technical level.

In their paper, they show that yes, secondary craters do dominate planetary surfaces, but for Mars (the object of interest at the moment), the critical diameter at which secondary craters dominate is about 1 km. Craters smaller than 1 km are likely >50% secondaries, but craters larger are >50% primaries. And because a significant amount of age dating is done with craters larger than 1 km, there is no way that “this whole foundation of … planetary dating [is in] disarray.”

The ICR article goes on from there, and either shows the author’s ignorance of the issues or that they are simply lying: “Without a way to reliably identify secondary craters …” As I stated above, the majority of secondary craters that are close to the primary can be identified because of their distinct shapes and characteristics – they are shallower, they are often elongated with the long axis pointing towards the primary, they appear in clusters, and there are generally trails of them that lead back to the primary. One could also ask the question, “If there were no ‘way to reliably identify secondary craters,’ then how could we know that there even are secondary craters?” Granted, it does become more difficult the farther from the primary crater and the smaller the secondary, but this becomes a non-issue when using large craters.

But, you can still use small craters to date planetary surfaces. One of the arguments used is that reference crater densities that indicate a certain age for a surface were created without taking secondary craters into account – in other words, they have both primary and secondary craters in them. So when using them to date a surface, it doesn’t matter if there are plenty of secondary craters there because they are in your reference, too.

Besides this, this topic is still in active debate at planetary astronomy conferences today (William Hartmann and Gerhard Neukum are two of the strongest proponents that secondary craters aren’t even an issue for sub-kilometer age dating). In fact, I was just at a conference – the Division of Planetary Science for the American Astronomical Society held at Cornell University in Ithaca, NY (October 2008) – where Dr. Hartmann presented results which indicated that secondary cratering is not a problem at sub-kilometer diameters for age dating.

In the last crater-related point I want to address from the article, it implies that astronomers applied crater age dating from the moon to other objects “believing they knew how old the earth-moon system was.” This is true, but it’s not true the way they imply it. From this statement (the next-to-last paragraph of the article), you are clearly meant to think that we used crater ages from the moon to go to other bodies, but if we don’t even know how many craters equals 1 year or 100 years or 1000 years on the moon, how could we possibly know what it means on other objects?

The answer should be apparent given the background I discussed above: Craters give relative ages, while radioactive decay dating methods give absolute ages. We applied the relative ages from the crater densities on the moon to other bodies, so it doesn’t really matter if we don’t know how old that surface is on the moon for that exercise. But then we can calibrate the relative scale with the absolute scale from the moon because we have independently dated its surface with a completely different method. Therefore, the ICR article is yet again trying to mislead the reader.

The final point that I would like to address is the article’s last sentence: “There is an important lesson here, though, for all science lovers: question assumptions.” (emphasis mine)

I whole-heartedly agree. You should question assumptions. You should try to understand why someone says what they do. You should do your own research, your own experiments, and make your own observations. You shouldn’t take my word for it, you shouldn’t take ICR’s word for it, you should go out and look for yourself.

Finally, you should always question someone’s assumptions, especially if they are based in an ideology: If they start from the premise that the Bible is Truth, the literal word of an omnipotent and infallible deity, and then try to make all observations fit within that view, you should be questioning that assumption.